Welcome to the forum Sasa. I don't know of any EU manufacturer making junk. It's cheaper to have that made in China so no point in it. With that said, a Fine Woodworking router bit test from 2007 rated Whiteside and Eagle America as the best (both made by Whiteside). Lee Valley's bits came in second, Infinity was 3rd I think. Several others scored better than CMT, Freud, or Amana which are the most common "top quality" bits. There are several manufacturers that weren't in the test so no way of knowing how they stack up, such as Onsrud, Leitz, Festool, Precision Bits (Yonico), and Oertli.
There are very few really junk bits being made anymore because every manufacturer I suspect is now using CNC machining.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.